Genotoxicity Induced by Cellular Uptake of Chitosan Nanoparticles in Human Dental Pulp Cells
Rami Alhomrany,
Chang Zhang,
Laisheng Chou
Issue:
Volume 10, Issue 4, July 2021
Pages:
79-86
Received:
4 June 2021
Accepted:
21 June 2021
Published:
15 July 2021
Abstract: Objective: Recent in vitro studies have shown that chitosan nanoparticles in several root canal sealers, intracanal medicament, and irrigation solutions could enhance the antimicrobial activity. However, the nanotoxicity of chitosan has not been fully studied. The aim of this study was to evaluate cellular uptake and genotoxicity of various sizes and concentrations of chitosan nanoparticles cultured with human dental pulp cells. Methods: Human dental pulp cells were derived from human dental pulp tissues and cultured for 24 hours with 50 nm and 318 nm FITC-tagged chitosan nanoparticles in concentrations: 0.1 mg/mL, 0.5 mg/mL, and 2 mg/mL as study groups, and 0 mg/mL as a control. The fluorescence intensity of the FITC tagged chitosan nanoparticles was measured using a spectrophotometer to determine the cellular uptake. Genotoxicity was assessed by the Cytokinesis-block micronucleus method and by measuring the fluorescent intensity of the phosphorylated H2AX nuclear foci. Statistical analysis was performed using One-Way ANOVA, post-hoc Tukey, and Chi-square tests. Results: Chitosan nanoparticles were able to internalize the human dental pulp cells and significantly induced micronuclei, nuclear buds, and pH2AX foci at concentrations of 0.5 mg/mL and 2 mg/mL as compared to 0.1 mg/mL (P < 0.01) and control group (P < 0.01). At both concentrations, 0.5 mg/mL and 2 mg/mL, 50 nm chitosan significantly induced higher proportions of micronuclei (P=0.001), nuclear buds (P=0.009), and pH2AX nuclear foci (P=0.00004) as compared to 318 nm chitosan. Conclusion: 50 nm and 318 nm chitosan nanoparticles at concentrations 0.5 mg/mL and 2 mg/mL penetrated human dental pulp cells and induced genotoxicity in dose-dependent and size-associated manners.
Abstract: Objective: Recent in vitro studies have shown that chitosan nanoparticles in several root canal sealers, intracanal medicament, and irrigation solutions could enhance the antimicrobial activity. However, the nanotoxicity of chitosan has not been fully studied. The aim of this study was to evaluate cellular uptake and genotoxicity of various sizes a...
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Improvement of the System of Diagnostics of Metal Structures and Mechanisms of Foundry Cranes
Pеnchuk Valentin Alekseevich,
Sidorov Vladimir Anatolyevich
Issue:
Volume 10, Issue 4, July 2021
Pages:
87-93
Received:
17 July 2021
Accepted:
2 August 2021
Published:
10 September 2021
Abstract: Periodic assessment of the technical condition of mechanisms and metal structures of foundry cranes is insufficient to ensure the reliability of the technogenic system of metallurgical production with long operating resources. Overviewing a crane as a set of rateresource elements with different recovery periods and regular control make it possible to set a range of optional and functional diagnostic parameters with regular inspection and constant control of technical condition of foundry cranes. The foundry crane is considered as an interaction of subsystems for which the operating conditions, characteristic damages and defects are determined. For diagnostics, the application of the following methods is considered: visual, visual-optical, vibration, thermal, non-destructive testing methods in the general structure of measures to maintain and restore the working condition of metallurgical cranes. Control and assessment of the condition of hawser, metal structures, lifting and movement mechanisms, automation systems are considered. The duplication of the strain monitoring system is carried out by the acceleration control system of metal structures – which allows to estimate the loads impact on the metal structure by the value of accelerations, which serves as the basis for the load cycle counter. The use of organoleptic methods, the installation of fixed systems and methods for periodic monitoring using portable instrumentation and multichannel systems, such as complex UMS-16 in conjunction with the SAFE PLANT allows to provide maintenance service information, prevents injuries, developing at different speeds.
Abstract: Periodic assessment of the technical condition of mechanisms and metal structures of foundry cranes is insufficient to ensure the reliability of the technogenic system of metallurgical production with long operating resources. Overviewing a crane as a set of rateresource elements with different recovery periods and regular control make it possible ...
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